This invention relates generally to voltage-regulating transformers and more specifically to voltage-regulating transformers of the ferro-resonant type.
Voltage-regulating ferro-resonant transformers are well known. These transformers comprise a primary winding, a tuned secondary circuit including the secondary winding, and an electromagnetic shunt. The output of the tuned secondary circuit is essentially constant. Within a normal range of input voltages, the secondary circuit resonates and drives the core into saturation. The flux produced by the primary voltage appears in the core or is switched through the shunt. Thus, the secondary voltage remains substantially constant notwithstanding changes in the input voltage.
Such prior voltage regulating transformers are bulky. Furthermore, magnetic circuits in which flux transfers between a closed core and an abutting or integral shunt are characterized by eddy current losses which reduce the overall transformer efficiency.
Therefore, it is an object of this invention to provide a compact ferro-resonant voltage regulating transformer.
It is a further object of the invention to increase the efficiency of a ferro-resonant voltage regulating transformer.
Yet another object of this invention is to provide a voltage regulating transformer with improved regulation.